China high quality 2.7cfm 30psi Oil Free Air Compressor Manufacturer for 5L Oxygen Concentrator mini air compressor

Product Description


Product Parameters

Complete solution leader in oilless air pump field

* Oilless operation
* Permanently lubricated bearings
* High performance piston seal
* Die-cast aluminum components
* Thin wall, hard coated aluminum cylinder
* Dynamically balanced
* Twin headed rock piston
* RoHS compliant
* Safety ETL certificated

NOTE: All test values are nominal and for reference only. They are not guaranteed maximum or minimum limits, nor do they imply mean or median.
Model Number    ZGK400-75/2-218
Performance Data
Head configuration Pressure parallel flow Pressure parallel flow
Nominal voltage/frequency 110V/60HZ 220V/50HZ
Current at rated load 4.1A 1.9A
Power at rated load 400W 390W
Flow at rated load 75L/MIN 75L/MIN
Pressure at rated load 30PSI(2BAR) 30PSI(2BAR)
Speed at rated load 1650RPM 1400RPM
Noise <55dB <55dB
Max.Pressure restart 0 PSI 0 PSI
Electrical Data
Motor type[Capacitance] P.S.C(30uF) P.S.C(10uF)
Motor insulation class B B
Thermal switch[Open temperature] Thermally protected(145°C) Thermally protected(145°C)
Line lead wire color,gauge White(hot),black(neutral),18AWG Brown(hot),blue(neutral),18AWG
Capacitor lead wire color,gauge Blue,blue,18AWG Black,black,18AWG
General Data
Operating ambient air temperature 50° to 104°F(10° to 40°C) 50° to 104°F(10° to 40°C)
Safety certification ETL ETL
Dimension(LXWXH) 234X102X168MM 234X102X168MM
Installation size 147X83.8MM
Net weight 6.5KG 6.5KG
Application For 5L oxygen concentrator use

Detailed Photos

Our Advantages



1.Standard product with ERB bearing, 14000 hours operation. 2.Customized imported TPI/NSK bearing


1.The coil adopts the fine pure copper enameled wire. 2.The rotor adopts the famous brand silicon steel sheet such as ZheJiang baosteel.


1.The valve steel of Sweden SANDVIK; Good flexibility and long durability. 2.Thickness from 0.08mm to 1.2mm, suitable for maximum pressure from 0.8 MPa to 1.2 MPa.

*Piston ring

1.Wear-resistant high temperature; Ensure more than 10,000 hours of service life. 2.Customized imported piston ring.

Product Application



Our manufacturing process


We design and produce all main parts by ourselves, along with the standard procedure and test equipment, so we can better control the quality and cost.Our factory starts from die-casting of aluminium, motor production, precision finishing, automatic assembly of pumps, the capacity is 300,000 units per month,we provide OEM/ODM service so that can better achieve high-end customization and development for customers.

Our company possess strong technical research and development force, owns self-design and new product development capabilities, we concentrate on building a “flagship type” enterprise with the whole series of product  lines of domestic and international medical use oilless air pumps.Technological innovation is the source of enterprise’s high quality development. We have a complete set of testing laboratories such as motor lab,high and low temperature lab,ROHS lab and Life test etc.

Our factory owns 8 motor production lines,16 aluminum die-casting machines, more than 150 high precision CNC lathes and more than 20 CNC machines. From the essential motor design to the entire design of the pump, it has been professionally tested, verified and validated, Our factory has full vertical integration for whole supply chain,So the quality can be firmly controlled by ourselves. 


Our Service




We specialize in the designing and manufacturing various kinds of oil free air compressor, vacuum pump since 2571,especially for medical applicaton,we are the vendor of Omron, Panasonic,Invacare, Nidek Medical etc.

Strive for survival by quality, seek benefits from management. Our company regards product quality as the life and continuous pursuit of the enterprise. Our company complies with the requirements of, implements the standardized management of R&D,production,quality assurance and production services, and sets up the strict operation specifications and procedures for each process. Our products have passed the ETL,CE,CCC and other certifications, CHINAMFG the leading level in the world.Our company has more than 20 invention patents and utility patents. Our company has acquired the certifications of “National High-Tech Enterprises”,”ZheJiang Private Science and Technology Enterprises”,”ZheJiang Engineering Technology Center” and so on.

We are dedicated to working with the global intelligent product brand owners, retailers and distributors to establish a CHINAMFG long-term OEM / ODM business partnerships.

Shipping Cost:

Estimated freight per unit.

To be negotiated
After-sales Service: on Line Support and Free Spare Parts
Thermal Protector: 145°c
Dimension: 234X102X168 mm
US$ 80/Piece
1 Piece(Min.Order)


Order Sample



air compressor

How does variable speed drive technology improve air compressor efficiency?

Variable Speed Drive (VSD) technology improves air compressor efficiency by allowing the compressor to adjust its motor speed to match the compressed air demand. This technology offers several benefits that contribute to energy savings and enhanced overall system efficiency. Here’s how VSD technology improves air compressor efficiency:

1. Matching Air Demand:

Air compressors equipped with VSD technology can vary the motor speed to precisely match the required compressed air output. Traditional fixed-speed compressors operate at a constant speed regardless of the actual demand, leading to energy wastage during periods of lower air demand. VSD compressors, on the other hand, ramp up or down the motor speed to deliver the necessary amount of compressed air, ensuring optimal energy utilization.

2. Reduced Unloaded Running Time:

Fixed-speed compressors often run unloaded during periods of low demand, where they continue to consume energy without producing compressed air. VSD technology eliminates or significantly reduces this unloaded running time by adjusting the motor speed to closely follow the air demand. As a result, VSD compressors minimize energy wastage during idle periods, leading to improved efficiency.

3. Soft Starting:

Traditional fixed-speed compressors experience high inrush currents during startup, which can strain the electrical system and cause voltage dips. VSD compressors utilize soft starting capabilities, gradually ramping up the motor speed instead of instantly reaching full speed. This soft starting feature reduces mechanical and electrical stress, ensuring a smooth and controlled startup, and minimizing energy spikes.

4. Energy Savings at Partial Load:

In many applications, compressed air demand varies throughout the day or during different production cycles. VSD compressors excel in such scenarios by operating at lower speeds during periods of lower demand. Since power consumption is proportional to motor speed, running the compressor at reduced speeds significantly reduces energy consumption compared to fixed-speed compressors that operate at a constant speed regardless of the demand.

5. Elimination of On/Off Cycling:

Fixed-speed compressors often use on/off cycling to adjust the compressed air output. This cycling can result in frequent starts and stops, which consume more energy and cause mechanical wear. VSD compressors eliminate the need for on/off cycling by continuously adjusting the motor speed to meet the demand. By operating at a consistent speed within the required range, VSD compressors minimize energy losses associated with frequent cycling.

6. Enhanced System Control:

VSD compressors offer advanced control capabilities, allowing for precise monitoring and adjustment of the compressed air system. These systems can integrate with sensors and control algorithms to maintain optimal system pressure, minimize pressure fluctuations, and prevent excessive energy consumption. The ability to fine-tune the compressor’s output based on real-time demand contributes to improved overall system efficiency.

By utilizing variable speed drive technology, air compressors can achieve significant energy savings, reduce operational costs, and enhance their environmental sustainability by minimizing energy wastage and optimizing efficiency.

air compressor

Are there differences between single-stage and two-stage air compressors?

Yes, there are differences between single-stage and two-stage air compressors. Here’s an in-depth explanation of their distinctions:

Compression Stages:

The primary difference between single-stage and two-stage air compressors lies in the number of compression stages they have. A single-stage compressor has only one compression stage, while a two-stage compressor has two sequential compression stages.

Compression Process:

In a single-stage compressor, the entire compression process occurs in a single cylinder. The air is drawn into the cylinder, compressed in a single stroke, and then discharged. On the other hand, a two-stage compressor utilizes two cylinders or chambers. In the first stage, air is compressed to an intermediate pressure in the first cylinder. Then, the partially compressed air is sent to the second cylinder where it undergoes further compression to reach the desired final pressure.

Pressure Output:

The number of compression stages directly affects the pressure output of the air compressor. Single-stage compressors typically provide lower maximum pressure levels compared to two-stage compressors. Single-stage compressors are suitable for applications that require moderate to low air pressure, while two-stage compressors are capable of delivering higher pressures, making them suitable for demanding applications that require greater air pressure.


Two-stage compressors generally offer higher efficiency compared to single-stage compressors. The two-stage compression process allows for better heat dissipation between stages, reducing the chances of overheating and improving overall efficiency. Additionally, the two-stage design allows the compressor to achieve higher compression ratios while minimizing the work done by each stage, resulting in improved energy efficiency.


Intercooling is a feature specific to two-stage compressors. Intercoolers are heat exchangers placed between the first and second compression stages. They cool down the partially compressed air before it enters the second stage, reducing the temperature and improving compression efficiency. The intercooling process helps to minimize heat buildup and reduces the potential for moisture condensation within the compressor system.


The choice between a single-stage and two-stage compressor depends on the intended application. Single-stage compressors are commonly used for light-duty applications such as powering pneumatic tools, small-scale workshops, and DIY projects. Two-stage compressors are more suitable for heavy-duty applications that require higher pressures, such as industrial manufacturing, automotive service, and large-scale construction.

It is important to consider the specific requirements of the application, including required pressure levels, duty cycle, and anticipated air demand, when selecting between a single-stage and two-stage air compressor.

In summary, the main differences between single-stage and two-stage air compressors lie in the number of compression stages, pressure output, efficiency, intercooling capability, and application suitability.

air compressor

How do oil-lubricated and oil-free air compressors differ?

Oil-lubricated and oil-free air compressors differ in terms of their lubrication systems and the presence of oil in their operation. Here are the key differences:

Oil-Lubricated Air Compressors:

1. Lubrication: Oil-lubricated air compressors use oil for lubricating the moving parts, such as pistons, cylinders, and bearings. The oil forms a protective film that reduces friction and wear, enhancing the compressor’s efficiency and lifespan.

2. Performance: Oil-lubricated compressors are known for their smooth and quiet operation. The oil lubrication helps reduce noise levels and vibration, resulting in a more comfortable working environment.

3. Maintenance: These compressors require regular oil changes and maintenance to ensure the proper functioning of the lubrication system. The oil filter may need replacement, and the oil level should be regularly checked and topped up.

4. Applications: Oil-lubricated compressors are commonly used in applications that demand high air quality and continuous operation, such as industrial settings, workshops, and manufacturing facilities.

Oil-Free Air Compressors:

1. Lubrication: Oil-free air compressors do not use oil for lubrication. Instead, they utilize alternative materials, such as specialized coatings, self-lubricating materials, or water-based lubricants, to reduce friction and wear.

2. Performance: Oil-free compressors generally have a higher airflow capacity, making them suitable for applications where a large volume of compressed air is required. However, they may produce slightly more noise and vibration compared to oil-lubricated compressors.

3. Maintenance: Oil-free compressors typically require less maintenance compared to oil-lubricated ones. They do not need regular oil changes or oil filter replacements. However, it is still important to perform routine maintenance tasks such as air filter cleaning or replacement.

4. Applications: Oil-free compressors are commonly used in applications where air quality is crucial, such as medical and dental facilities, laboratories, electronics manufacturing, and painting applications. They are also favored for portable and consumer-grade compressors.

When selecting between oil-lubricated and oil-free air compressors, consider the specific requirements of your application, including air quality, noise levels, maintenance needs, and expected usage. It’s important to follow the manufacturer’s recommendations for maintenance and lubrication to ensure the optimal performance and longevity of the air compressor.

China high quality 2.7cfm 30psi Oil Free Air Compressor Manufacturer for 5L Oxygen Concentrator   mini air compressorChina high quality 2.7cfm 30psi Oil Free Air Compressor Manufacturer for 5L Oxygen Concentrator   mini air compressor
editor by CX 2023-09-28

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